Tilbage til slide -- Tastaturgenvej: 'u'  forrige -- Tastaturgenvej: 'p'                functions/eq-sec-degree.c - En funktion der finder rødder i en andengradsligning.Lektion 5 - slide 5 : 30
Program 2

#include <stdio.h>
#include <math.h>

/* Find and print the roots in a * x*x + b * x + c = 0 */
void solveQuadraticEquation(void){
  double a, b, c, discriminant;

  printf("Enter coeficients a, b, and c (a != 0): ");
  scanf("%lf %lf %lf", &a, &b, &c);

  discriminant = b * b - 4 * a * c;

  if (discriminant < 0)
    printf("No roots\n");
  else if (discriminant == 0)
    printf("One root: %f\n", -b/(2*a));
  else 
    printf("Two roots: %f and %f\n",
           (-b + sqrt(discriminant))/(2*a), 
           (-b - sqrt(discriminant))/(2*a) );
}   

int main(void) {
  int i = 3;

  /* ... */

  /* Solve three equations:   */
  for (i = 1; i <= 3; i++)
    solveQuadraticEquation();  

  /* ... */

  return 0;
}